| In order to explore the effect of desulfurized gypsum on the infiltration process of saline\|sodic soils, a soil column infiltration experiment was conducted with 5 desulfurized gypsum application levels (0.0, 0.5%, 1.0%, 1.5%, and 2.0% of soil by weight) in June 2020. The ion composition of the tested soil was mainly Na2CO3 and NaHCO3 with 1.89 mS·cm-1 of the EC, 10.01 of the SAR, and 40.20% of ESP. Two infiltration models of Philip and Kostiakov were used to describe the process of soil moisture infiltration. The results showed that when the infiltration time was 630 min, the cumulative infiltration of 0.5%, 1.0%, 1.5%, and 2.0% treatments increased by 20.00%, 43.03%, 61.21%, and 55.15%, and the infiltration rate increased by 64.94%, 233.33%, 271.86%, and 339.83%, respectively, compared with 0.0% treatment. When the wetting front was moved to 60 cm, the time of 0.5%, 1.0%, 1.5%, and 2.0% treatments decreased by 33.33%, 63.89%, 63.89%, and 70.83%, respectively, compared with that of 0.0%. Meantime, desulfurized gypsum significantly affected the parameters of the infiltration formula of Philip and Kostiakov. The absorption rate, S, reached 0.0957 from 0.0647 cm·min-0.5, the stable infiltration rate, A, reached 0.0189 from 0.0024 cm·min-1, and the experience coefficient, K, reached 0.0165 from 0.0698 with increasing the amount of desulfurized gypsum application. At the depth of 50 cm to 60 cm, as the amount of desulfurization gypsum increased, the EC gradually increased, and the efficiency of soil desalination increased. In summary, desulfurized gypsum sped up the infiltration rate of alkaline soil water, increased the efficiency of desalination, and had a significant effect on the amelioration of saline\|sodic soils. |